U.S. patent number 11,212,058 [Application Number 16/632,725] was granted by the patent office on 2021-12-28 for command acknowledgment in a wireless communication system.
This patent grant is currently assigned to Telefonaktiebolaget LM Ericsson (publ). The grantee listed for this patent is Telefonaktiebolaget LM Ericsson (publ). Invention is credited to Marco Belleschi, Mattias Bergstrom.
United States Patent |
11,212,058 |
Belleschi , et al. |
December 28, 2021 |
Command acknowledgment in a wireless communication system
Abstract
A user equipment (105), UE, is configured for use in a wireless
communication system (100). The UE (105) acknowledges one or more
first commands received from an access node (110) by transmitting,
to the access node (110), a first acknowledgment comprising a
confirmation field set to a first value. After acknowledging the
one or more first commands, the UE (105) acknowledges one or more
second commands received from the access node (110) by selectively
transmitting or refraining from transmitting, to the access node
(110), a second acknowledgement comprising the confirmation field
set to a second value depending respectively on whether or not the
second value would be different from the first value.
Inventors: |
Belleschi; Marco (Solna,
SE), Bergstrom; Mattias (Sollentuna, SE) |
Applicant: |
Name |
City |
State |
Country |
Type |
Telefonaktiebolaget LM Ericsson (publ) |
Stockholm |
N/A |
SE |
|
|
Assignee: |
Telefonaktiebolaget LM Ericsson
(publ) (Stockholm, SE)
|
Family
ID: |
1000006021640 |
Appl.
No.: |
16/632,725 |
Filed: |
August 9, 2018 |
PCT
Filed: |
August 09, 2018 |
PCT No.: |
PCT/SE2018/050805 |
371(c)(1),(2),(4) Date: |
January 21, 2020 |
PCT
Pub. No.: |
WO2019/032029 |
PCT
Pub. Date: |
February 14, 2019 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20210152315 A1 |
May 20, 2021 |
|
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
62544350 |
Aug 11, 2017 |
|
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04L
5/0055 (20130101); H04W 48/14 (20130101); H04W
48/16 (20130101); H04W 72/0406 (20130101) |
Current International
Class: |
H04L
5/00 (20060101); H04W 48/16 (20090101); H04W
48/14 (20090101); H04W 72/04 (20090101); H04L
1/16 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
2016041203 |
|
Mar 2016 |
|
WO |
|
2017078128 |
|
May 2017 |
|
WO |
|
2018174770 |
|
Sep 2018 |
|
WO |
|
2010088680 |
|
Aug 2020 |
|
WO |
|
Primary Examiner: Cho; Hong S
Attorney, Agent or Firm: Sage Patent Group
Parent Case Text
RELATED APPLICATIONS
This application claims priority to U.S. Provisional Patent
Application Ser. No. 62/544,350, filed 11 Aug. 2017, the entire
contents of which are herein incorporated by reference.
Claims
The invention claimed is:
1. A method performed by a user equipment (UE) configured for use
in a wireless communication system, the method comprising:
acknowledging one or more first commands received from an access
node by transmitting, to the access node, a first acknowledgment
comprising a confirmation field set to a first value; and after
acknowledging the one or more first commands, acknowledging one or
more second commands received from the access node by selectively
transmitting or refraining from transmitting, to the access node, a
second acknowledgement comprising the confirmation field set to a
second value depending respectively on whether or not the second
value would be different from the first value.
2. The method of claim 1, wherein acknowledging the one or more
first commands and acknowledging the one or more second commands is
performed at respective acknowledgement transmission opportunities
granted by the access node.
3. The method of claim 1, further comprising toggling one or more
bits of the confirmation field responsive to receiving each of the
first and second commands.
4. The method of claim 1, wherein at least one of the first and
second commands is a command to activate or release an operating
configuration specifying a set of transmission parameters for
communication.
5. The method of claim 1, wherein: transmitting the first
acknowledgement comprises transmitting the first acknowledgement
with the confirmation field set to zero; and selectively
transmitting or refraining from transmitting the second
acknowledgement comprises transmitting the second acknowledgement
with the confirmation field set to one.
6. The method of claim 1, wherein the confirmation field is a
single bit field.
7. A method performed by an access node configured for use in a
wireless communication system, the method comprising: transmitting
a first set of commands to a user equipment, UE, and receiving a
first acknowledgement from the UE in response, the first
acknowledgement comprising a confirmation field set to a first
value; and scheduling transmission of a second set of commands to
the UE according to one or more rules that require the UE to
respond with a second acknowledgement comprising the confirmation
field set to a second value that is different from the first value,
wherein at least one of the first and second commands is a command
to activate or release an operating configuration specifying a set
of transmission parameters for communication.
8. The method of claim 7, wherein the confirmation field is a
single bit field.
9. The method of claim 7, wherein the first value is zero and the
second value is one.
10. A user equipment (UE) configured for use in a wireless
communication system, the UE comprising: a communication circuitry
configured to exchange signals with the wireless communication
system; and a processing circuitry communicatively coupled to the
communication circuitry and configured to: acknowledge one or more
first commands received from an access node by transmitting, to the
access node, a first acknowledgment comprising a confirmation field
set to a first value; and after acknowledging the one or more first
commands, acknowledge one or more second commands received from the
access node by selectively transmitting or refraining from
transmitting, to the access node, a second acknowledgement
comprising the confirmation field set to a second value depending
respectively on whether or not the second value would be different
from the first value.
11. The UE of claim 10, wherein the processing circuitry is
configured to acknowledge the one or more first commands and
acknowledge the one or more second commands at respective
acknowledgement transmission opportunities granted by the access
node.
12. The UE of claim 10, wherein the processing circuitry is further
configured to toggle one or more bits of the confirmation field
responsive to receiving each of the first and second commands.
13. The UE of claim 10, wherein at least one of the first and
second commands is a command to activate or release an operating
configuration specifying a set of transmission parameters for
communication.
14. The UE of claim 10, wherein: to transmit the first
acknowledgement the processing circuitry is configured to transmit
the first acknowledgement with the confirmation field set to zero;
and to selectively transmit or refrain from transmitting the second
acknowledgement the processing circuitry is configured to select
transmitting the second acknowledgement with the confirmation field
set to one.
15. The UE of claim 10, wherein the confirmation field is a single
bit field.
16. An access node configured for use in a wireless communication
system, the access node comprising: communication circuitry
configured to exchange signals with the wireless communication
system; processing circuitry communicatively coupled to the
communication circuitry and configured to: transmit a first set of
commands to a user equipment, UE, and receiving a first
acknowledgement from the UE in response, the first acknowledgement
comprising a confirmation field set to a first value; and schedule
transmission of a second set of commands to the UE according to one
or more rules that require the UE to respond with a second
acknowledgement comprising the confirmation field set to a second
value that is different from the first value, wherein at least one
of the first and second commands is a command to activate or
release an operating configuration specifying a set of transmission
parameters for communication.
17. The access node of claim 16, wherein the confirmation field is
a single bit field.
18. The access node of claim 16, wherein the first value is zero
and the second value is one.
Description
TECHNICAL FIELD
The present disclosure generally relates to the field of wireless
communication networks, and more particularly relates to signaling
schemes useful for acknowledging one or more commands received from
a remote device.
BACKGROUND
In wireless communication networks, there may be a number of
situations in which a base station (e.g., eNB, gNB) provides a User
Equipment (UE) with certain commands, the reception of which the UE
is required to confirm/acknowledge. For example, the base station
may rely on these acknowledgements to determine whether or not to
retransmit the commands. For purposes of this disclosure, an
acknowledgement may also be referred to as a confirmation (e.g.,
acknowledging receipt of a command may alternatively be referred to
as confirming receipt of a command, and vice versa).
SUMMARY
Embodiments of the present disclosure include various methods,
apparatus, systems, computer readable media, computer program
products, and/or carriers. In general, such embodiments relate to
signaling schemes useful for acknowledging one or more commands
received from a remote device.
Particular embodiments include a method performed by a UE. The UE
is configured for use in a wireless communication system. The
method comprises acknowledging one or more first commands received
from an access node by transmitting, to the access node, a first
acknowledgment comprising a confirmation field set to a first
value. The method further comprises, after acknowledging the one or
more first commands, acknowledging one or more second commands
received from the access node by selectively transmitting or
refraining from transmitting, to the access node, a second
acknowledgement comprising the confirmation field set to a second
value depending respectively on whether or not the second value
would be different from the first value.
In some embodiments, acknowledging the one or more first commands
and acknowledging the one or more second commands is performed at
respective acknowledgement transmission opportunities granted by
the access node.
In some embodiments, the method further comprises toggling one or
more bits of the confirmation field responsive to receiving each of
the first and second commands.
In some embodiments, at least one of the first and second commands
is a command to activate or release an operating configuration
specifying a set of transmission parameters for communication. In
some such embodiments, the operating configuration specifies a set
of periodic radio resources for uplink communication.
In some embodiments, transmitting the first acknowledgement
comprises transmitting the first acknowledgement with the
confirmation field set to zero, and selectively transmitting or
refraining from transmitting the second acknowledgement comprises
transmitting the second acknowledgement with the confirmation field
set to one.
In some embodiments, the confirmation field is shared for
confirming receipt of any command to activate or release any of
multiple operating configurations in a specific cell. In some other
embodiments, the confirmation field is shared for confirming
receipt of any command to activate or release any of multiple
operating configurations for a plurality of different cells.
In some embodiments, the confirmation field is a single bit
field.
Other embodiments include a different method performed by a UE. The
UE is configured for use in a wireless communication system. The
method comprises receiving, from an access node, an indication of a
number of commands that will be transmitted from the access node to
the UE. The method further comprises selectively transmitting or
refraining from transmitting an acknowledgement message to the
access node depending respectively on whether or not the UE
receives the indicated number of commands within a downlink time
interval to which the indication of the number of commands
applies.
In some embodiments, the method further comprises receiving at
least one command to activate or release an operating configuration
specifying a set of transmission parameters for communication. In
some such embodiments, the operating configuration specifies a set
of periodic radio resources for uplink communication.
In some embodiments, the acknowledgement message comprises a
confirmation field that is shared for confirming receipt of any
command to activate or release any of multiple operating
configurations in a specific cell. In some other embodiments, the
acknowledgement message comprises a confirmation field that is
shared for confirming receipt of any command to activate or release
any of multiple operating configurations for a plurality of
different cells. In some embodiments of either case, the
confirmation field is set to zero or one based on a number of
commands received within the downlink time interval. Additionally
or alternatively, according to embodiments, the confirmation field
is a single bit field.
In some embodiments, the indication of the number of commands is
received in radio resource control (RRC) signaling.
In some embodiments, the indication of the number of commands is
received in a medium access control (MAC) control element (CE).
In some embodiments, the indication of the number of commands is
received in downlink control information.
Other embodiments include a method performed by an access node. The
access node is configured for use in a wireless communication
system. The method comprises transmitting, to a user equipment, UE,
one or more first commands and subsequently one or more second
commands. The method further comprises determining that the UE
received the one or more first commands by receiving, from the UE,
a first acknowledgement comprising a confirmation field set to a
first value. The method further comprises determining that the UE
received the one or more second commands by receiving or not
receiving, from the UE, a second acknowledgement comprising the
confirmation field set to a second value depending respectively on
whether or not the second value would be different from the first
value.
In some embodiments, at least one of the first and second commands
is a command to activate or release an operating configuration
specifying a set of transmission parameters for communication. In
some such embodiments the operating configuration specifies a set
of periodic radio resources for uplink communication.
In some embodiments, the confirmation field is shared for
confirming receipt of any command to activate or release any of
multiple operating configurations in a specific cell. In some other
embodiments, the confirmation field is shared for confirming
receipt of any command to activate or release any of multiple
operating configurations for a plurality of different cells.
In some embodiments, the confirmation field is a single bit
field.
In some embodiments, the first value is zero and the second value
is one.
Yet other embodiments include a different method performed by an
access node. The access node is configured for use in a wireless
communication system. The method comprises transmitting a first set
of commands to a user equipment, UE, and receiving a first
acknowledgement from the UE in response, the first acknowledgement
comprising a confirmation field set to a first value. The method
further comprises scheduling transmission of a second set of
commands to the UE according to one or more rules that require the
UE to respond with a second acknowledgement comprising the
confirmation field set to a second value that is different from the
first value.
In some embodiments, at least one of the first and second commands
is a command to activate or release an operating configuration
specifying a set of transmission parameters for communication. In
some such embodiments the operating configuration specifies a set
of periodic radio resources for uplink communication.
In some embodiments, the confirmation field is shared for
confirming receipt of any command to activate or release any of
multiple operating configurations in a specific cell. In some other
embodiments, the confirmation field is shared for confirming
receipt of any command to activate or release any of multiple
operating configurations for a plurality of different cells.
In some embodiments, the confirmation field is a single bit
field.
In some embodiments, the first value is zero and the second value
is one.
Yet further embodiments include a UE configured for use in a
wireless communication system. The UE is configured to acknowledge
one or more first commands received from an access node by
transmitting, to the access node, a first acknowledgment comprising
a confirmation field set to a first value. The UE is further
configured to, after acknowledging the one or more first commands,
acknowledge one or more second commands received from the access
node by selectively transmitting or refraining from transmitting,
to the access node, a second acknowledgement comprising the
confirmation field set to a second value depending respectively on
whether or not the second value would be different from the first
value.
In some embodiments, the UE comprises a processor and a memory, the
memory containing instructions executable by the processor whereby
the device is operative to configure the UE.
In some embodiments, the UE comprises a first acknowledging module
configured to acknowledge the one or more first commands, and a
second acknowledging module configured to acknowledge the one or
more second commands.
In some embodiments, the UE is configured to perform one or more of
the methods described above.
Yet further embodiments include another UE configured for use in a
wireless communication system. The UE is configured to receive,
from an access node, an indication of a number of commands that
will be transmitted from the access node to the UE. The UE is
further configured to selectively transmit or refrain from
transmitting an acknowledgement message to the access node
depending respectively on whether or not the UE receives the
indicated number of commands within a downlink time interval to
which the indication of the number of commands applies.
In some embodiments, the UE comprises a processor and a memory, the
memory containing instructions executable by the processor whereby
the device is operative to configure the UE.
In some embodiments, the UE comprises a receiving module configured
to receive the indication of the number of commands, and a
transmitting module configured to selectively transmit or refrain
from transmitting the acknowledgement message to the access
node.
In some embodiments, the UE is configured to perform one or more of
the methods described above.
Yet further embodiments include an access node configured for use
in a wireless communication system. The access node is configured
to transmit, to a UE, one or more first commands and subsequently
one or more second commands. The access node is further configured
to determine that the UE received the one or more first commands by
receiving, from the UE, a first acknowledgement comprising a
confirmation field set to a first value. The access node is further
configured to determine that the UE received the one or more second
commands by receiving or not receiving, from the UE, a second
acknowledgement comprising the confirmation field set to a second
value depending respectively on whether or not the second value
would be different from the first value.
In some embodiments, the access node comprises a processor and a
memory, the memory containing instructions executable by the
processor whereby the device is operative to configure the access
node.
In some embodiments, the access node comprises a transmitting
module configured to transmit, to the UE, the one or more first
commands and subsequently the one or more second commands, a first
determining module configured to determine that the UE received the
one or more first commands, and a second determining module
configured to determine that the UE received the one or more second
commands.
In some embodiments, the access node is configured to perform one
or more of the methods described above.
Yet further embodiments include another access node configured for
use in a wireless communication system. The access node is
configured to transmit a first set of commands to a UE, and receive
a first acknowledgement from the UE in response, the first
acknowledgement comprising a confirmation field set to a first
value. The access node is further configured to schedule
transmission of a second set of commands to the UE according to one
or more rules that require the UE to respond with a second
acknowledgement comprising the confirmation field set to a second
value that is different from the first value.
In some embodiments, the access node comprises a processor and a
memory, the memory containing instructions executable by the
processor whereby the device is operative to configure the access
node.
In some embodiments, the access node comprises an interfacing
module configured to transmit the first set of commands and receive
the first acknowledgement from the UE in response, and a scheduling
module configured to schedule the transmission of the second set of
commands.
In some embodiments, the access node is configured to perform one
or more of the methods described above.
Yet further embodiments include a computer program, comprising
instructions which, when executed on at least one processor of a
network device, cause the at least one processor to carry out any
of the methods described above.
Yet further embodiments include a carrier containing such a
computer program, the carrier being one of an electronic signal,
optical signal, radio signal, or computer readable storage
medium.
BRIEF DESCRIPTION OF THE DRAWINGS
Aspects of the present disclosure are illustrated by way of example
and are not limited by the accompanying figures with like
references indicating like elements. In general, the use of a
reference numeral should be regarded as referring to the depicted
subject matter generally, whereas discussion of a specific instance
of an illustrated element will append a letter designation thereto
(e.g., discussion of an UE 105, generally, as opposed to discussion
of particular instances of UEs 105a, 105b).
FIG. 1 is a block diagram illustrating an example of a wireless
communication network, according to one or more embodiments of the
present disclosure.
FIG. 2 is a block diagram illustrating an example time-frequency
grid of physical resources used for wireless communication,
according to one or more embodiments of the present disclosure.
FIG. 3 is a block diagram illustrating an example radio frame,
according to one or more embodiments of the present disclosure.
FIG. 4 is a flow diagram illustrating an example method, according
to one or more embodiments of the present disclosure.
FIG. 5 is a flow diagram illustrating another example method,
according to one or more embodiments of the present disclosure.
FIG. 6 is a flow diagram illustrating yet another example method,
according to one or more embodiments of the present disclosure.
FIGS. 7A and 7B are state diagrams, each of which illustrates a
respective example scheme for selectively transmitting or
refraining from transmitting, according to one or more embodiments
of the present disclosure.
FIG. 8 is a flow diagram illustrating a yet further example method,
according to one or more embodiments of the present disclosure.
FIG. 9 is a block diagram illustrating example hardware, according
to one or more embodiments of the present disclosure.
FIG. 10-12 are block diagrams, each of which illustrates example
components, according to one or more embodiments of the present
disclosure.
FIG. 13 is a flow diagram illustrating an additional example
method, according to one or more embodiments of the present
disclosure.
FIG. 14 is a block diagram illustrating further example components,
according to one or more embodiments of the present disclosure.
DETAILED DESCRIPTION
FIG. 1 illustrates an example communication system 100 according to
one or more embodiments of the present disclosure. Although certain
aspects of the communication system 100 may herein be described in
the context of a Long-Term Evolution (LTE) communication network,
the discussion throughout this disclosure may similarly be applied
to other wireless communication systems and/or combinations
thereof, including but not limited to 5G Next Radio (NR) and/or
Wi-Fi.
The communication system 100 comprises a plurality of wireless
communication nodes. One of the wireless communication nodes in
particular is an access node 110 that serves a cell 115 to User
Equipments (UEs) 105a-b. The UEs 105a-b and/or access node may, in
some embodiments, each be referred to as a radio node (i.e., a
network node capable of radio communication). Further, the access
node 110 may be referred to, in some embodiments, as a base station
(such as an eNB, gNB), for example. Although only one access node
110 and two UEs 105a-b are illustrated in FIG. 1, other examples of
the communication system 100 may include any number of access nodes
110, each of which may serve one or more cells 115 to any number of
UEs 105. Further, according to other embodiments, the UEs 105a-b
may, instead, be base stations (e.g., femtocells, relay base
stations).
Wireless communication between the access node 110 and each of the
UEs 105a-b is performed using radio resources across a time domain,
a frequency domain, or both. LTE in particular uses OFDM in the
downlink and Discrete Fourier Transform (DFT) spread OFDM in the
uplink. The basic LTE downlink physical resource can be viewed as a
time-frequency grid. FIG. 2 illustrates a portion of an example
OFDM time-frequency grid 50 for LTE. Generally speaking, the
time-frequency grid 50 is divided into one millisecond subframes.
Each subframe includes a number of OFDM symbols. For a normal
cyclic prefix (CP) length, suitable for use in situations where
multipath dispersion is not expected to be extremely severe, a
subframe may comprise fourteen OFDM symbols. A subframe may
comprise twelve OFDM symbols if an extended cyclic prefix is used.
In the frequency domain, the physical resources shown in FIG. 2 are
divided into adjacent subcarriers with a spacing of 15 kHz. The
number of subcarriers may vary according to the allocated system
bandwidth. The smallest element of the time-frequency grid 50 is
typically referred to as a resource element, which comprises one
OFDM subcarrier during one OFDM symbol interval.
In LTE systems, data is transmitted to a UE 105 over a downlink
transport channel known as the Physical Downlink Shared Channel
(PDSCH). The PDSCH is a time and frequency multiplexed channel
shared by a plurality of UEs 105. As shown in FIG. 3, the downlink
transmissions are typically organized into ten millisecond radio
frames 60. Each radio frame typically comprises ten equally-sized
subframes 62. For purposes of scheduling users to receive downlink
transmissions, the downlink time-frequency resources are allocated
in units called resource blocks (RBs). Each resource block
typically spans twelve subcarriers (which may be adjacent or
distributed across the frequency spectrum) and one 0.5 ms slot (one
half of one subframe).
Within a cell 115 the access node 110 may dynamically schedule
downlink transmissions to and/or uplink transmissions from one or
more of the UEs 105a-b, according to one or more embodiments. For
such dynamic scheduling, the scheduling node 110 may transmit
downlink control information (DCI) in each subframe 62. The DCI
identifies one or more UEs 105 that have been scheduled to receive
data in the current downlink subframe 62 and the resource blocks on
which the data is being transmitted to the scheduled radio nodes
105. The DCI is typically transmitted on the Physical Downlink
Control Channel (PDCCH), e.g., in the first two, three, or four
OFDM symbols in each subframe 62. The resources on which the data
is carried is typically transmitted in a corresponding Physical
Downlink Shared Channel (PDSCH).
The access node 110 may additionally or alternatively perform
semi-persistent scheduling (SPS) of the downlink and/or uplink,
according to one or more embodiments. SPS generally requires less
signaling overhead than dynamic scheduling. For SPS scheduling, the
resource blocks on which data is being transmitted to one or more
radio nodes 105 is not identified in DCI transmitted in each
subframe 62 (as is the case in dynamic scheduling). Rather, the
resource blocks may be identified in DCI transmitted in a
particular subframe 62 for multiple subframes (e.g., the present
subframe and one or more subsequent subframes). According to one or
more embodiments, the multiple subframes may be contiguous or
discontiguous. The spacing between subframe occasions to which the
DCI applies may, in some embodiments, be a periodicity of the SPS.
This SPS period may be expressed in terms of time (e.g., every 10
milliseconds) and/or in terms of subframes (e.g., every tenth
subframe). According to embodiments, this period may be adapted by
the access node 110, e.g., by appropriate signaling as will be
discussed below. Further, this period may be of a duration that is
less than, equal to, or greater than the duration of a radio frame
60, according to various embodiments.
According to embodiments, the access node 110 may freely switch
between dynamic scheduling and SPS, and may configure one or more
UEs 105 accordingly (e.g., via Radio Resource Control (RRC)
signaling to indicate that SPS of a particular periodicity is to be
used). Thereafter, the access node 110 may send a command (e.g., in
DCI) to a UE 105 to activate SPS. The UE 105 may store this DCI and
expect a downlink transmission at each SPS occasion accordingly.
Similarly, the access node 110 may send a command (e.g., in DCI) to
a UE 105 to release the UE 105 from this SPS configuration.
The UE 105 may, in some embodiments, acknowledge a previously
received command (e.g., an activation command, a release command, a
reactivation command). Such embodiments may include, for example,
the network 100 sending (e.g., via an access node 110 to the UE
105) an activation or deactivation command for cellular operations
in different cells 115, e.g., to indicate that the UE 105 should
start or stop using a certain cell 115, or to indicate that SPS or
other cellular features should or should not be used on a certain
cell 115. For example, the network may send SPS activation and/or
release commands to the UE 105 to activate and/or release certain
SPS configurations in certain cells 115.
Other embodiments may include, for example, the network 100 sending
(e.g., via the access node 110 to the UE 105) activation and/or
deactivation commands for certain operating configurations
previously provided by the network 100. In particular, each of
these operating configurations may correspond to a different set of
transmitting parameters including, e.g., time/frequency
resource(s), Modulation and Coding Scheme (MCS), power, Hybrid
Automatic Repeat reQuest (HARQ) configuration(s), beam
configuration(s), antenna configuration(s), etc. Accordingly, each
of these operating configurations may be addressed by a
configuration index. In this case, the network 100 may need to
specifically address the operating configuration via its related
index in order to activate and/or release it and the UE 105 may
need to acknowledge the correct reception of the command pertaining
to the indicated configuration. According to a particular example,
a first operating configuration may include a specific SPS
configuration, whereas a second operating configuration may include
a pool of time resources represented by a bitmap in which each bit
indicates whether a certain subframe may be used by the UE 105 for
transmission.
One example in which the UE 105 may acknowledge a command may be by
toggling a certain signaled bit between 0 and 1 whenever a command
requiring acknowledgement is received. For example, the UE 105 may
support transmission of an acknowledgement message that comprises a
confirmation field comprising one or more bits. Each of the bits
may, in some embodiments, correspond to a cell and/or type of
setting that is configurable by the access node 110. According to
one example in which each bit corresponds to a respective cell, the
UE may acknowledge a command from the access node 110 that
activates or deactivates an operating configuration in a given cell
115 by transmitting an acknowledgement message in which the bit of
the confirmation field that corresponds to the given cell 115 is
toggled (e.g., as compared to the value of that bit as transmitted
in a previous acknowledgement message). Such an acknowledgement
message may inform the access node 110 that the command has been
correctly received for the given cell 115.
According to other embodiments, each of the bits may correspond to
a respective operating configuration. In such an example, the UE
105 may acknowledge a command from the access node 110 that
activates or deactivates a given operating configuration by
transmitting an acknowledgement message in which the bit of the
confirmation field that corresponds to the given operating
configuration is toggled (e.g., as compared to the value of that
bit as transmitted in a previous acknowledgement message). Such an
acknowledgement message may inform the network that the command has
been correctly received for the given cell 115.
In certain embodiments, the bit toggling mechanism discussed above
may result in ambiguity with respect to what exactly was intended
to be acknowledged by the UE 105. For example, the access node 110
may attempt to simultaneously activate and/or release a set of two
operating configurations with respect to a given cell 115 (e.g., in
the same DCI). The UE 105, using the above-discussed bit toggling
mechanism to acknowledge commands, may first toggle the bit of the
confirmation field corresponding to the given cell from 0 to 1 and
then again from 1 to 0 before sending the acknowledgement message,
thereby leading to ambiguity with respect to whether the 0 value
indicates that both commands were received, or that neither of the
commands were received. In other words, according to this example,
if an acknowledgement message is sent to the access node 110
including a 0 in the bit for the given cell 115, the access node
110 receiving this 0 bit may interpret the value of this bit as
having not been toggled (e.g., because the activation and/or
deactivation commands were not received). Similar problems may
manifest when the access node 110 activates/releases other even
numbers of operating configurations via corresponding commands when
the UE 105 uses the above-discussed bit toggling acknowledgement
scheme.
In a similar example, the access node 110 may attempt to
simultaneously activate and/or release three operating
configurations with respect to a given cell 115. In such an
example, the UE 105, using the above-discussed bit toggling
mechanism to acknowledge commands, may first toggle the bit for a
given cell 115 from 0 to 1 for the first operating configuration,
then from 1 to 0 for the second operating configuration, and
finally from 0 to 1 for the third operating configuration before
sending the acknowledgement message. The access node 110, receiving
a value of 1 for the bit corresponding to the given cell 115 in the
confirmation field of the acknowledgment message may not be able to
determine whether only one of the commands was correctly received
or whether all three were correctly received. Further, if the 1 bit
is intended to indicate that only one command was correctly
received, the access node 110 may not be able to determine which of
the three commands was correctly received (and correspondingly,
which of the three operating configurations the UE 105 intends to
activate and/or release). Similar problems may manifest when the
access node 110 activates and/or releases other odd numbers of
operating configurations via corresponding commands when the UE 105
uses the above-discussed bit toggling acknowledgement scheme.
Particular embodiments of the present disclosure resolve or avoid
the above discussed ambiguity in the acknowledgement messages
transmitted by a UE 105 in response to receiving one or more
commands for operation in different cells and/or for different
operating configurations. Particular embodiments include various
methods to determine whether to transmit or refrain from
transmitting an acknowledgement message in which once at least one
bit is toggled more than once in the acknowledgement message, for
example. Other embodiments schedule transmission of commands in
accordance with one or more rules that require the UE 105 to
transmit acknowledgements that have their confirmation fields set
to different values.
One particular embodiment of the present disclosure includes the
method 400 illustrated in FIG. 4. The method 400 is performed by a
UE 105 configured for use in a wireless communication system 100.
The method 400 comprises acknowledging one or more first commands
received from an access node 110 by transmitting, to the access
node 110, a first acknowledgment comprising a confirmation field
set to a first value (block 410). The method further comprises,
after acknowledging the one or more first commands, acknowledging
one or more second commands received from the access node 110 by
selectively transmitting or refraining from transmitting, to the
access node 110, a second acknowledgement comprising the
confirmation field set to a second value depending respectively on
whether or not the second value would be different from the first
value (block 420).
Another particular embodiment of the present disclosure includes
the method 500 illustrated in FIG. 5. The method 500 is performed
by an access node 110 configured for use in a wireless
communication system 100. The method 500 comprises transmitting, to
a UE 105, one or more first commands and subsequently one or more
second commands (block 510). The method 500 further comprises
determining that the UE 105 received the one or more first commands
by receiving, from the UE 105, a first acknowledgement comprising a
confirmation field set to a first value (block 520). The method 500
further comprises determining that the UE 105 received the one or
more second commands by receiving or not receiving, from the UE
105, a second acknowledgement comprising the confirmation field set
to a second value depending respectively on whether or not the
second value would be different from the first value (block
530).
Yet another particular embodiment of the present disclosure
includes the method 600 illustrated in FIG. 6. The method 600 is
performed by an access node 110 configured for use in a wireless
communication system 100. The method 600 comprises transmitting a
first set of commands to a UE 105 and receiving a first
acknowledgement from the UE 105 in response. The first
acknowledgement comprises a confirmation field set to a first
value. The method 600 further comprises scheduling transmission of
a second set of commands to the UE 105 according to one or more
rules that require the UE 105 to respond with a second
acknowledgement comprising the confirmation field set to a second
value that is different from the first value.
According to various embodiments, the UE 105 may deliver the
acknowledgement message via RRC, Medium Access Control (MAC) (such
as in a MAC Control Element (CE)), Physical Uplink Shared Channel
(PUSCH), or Physical Uplink Control Channel (PUCCH), for example.
The acknowledgement message includes some number of bits, each of
which may, for example, represent a respective cell index. In such
an embodiment, the value of a particular bit may indicate
acknowledgement of a command (e.g., an activation command, a
release command) pertaining to the corresponding cell.
Alternatively, each of the bits may represent, for example, the
index of a given operating configuration. In such an embodiment,
the value of a particular bit may indicate acknowledgement of a
command pertaining to the corresponding operating configuration. An
example of such an operating configuration may be a specific SPS
configuration in which certain time/frequency resources are to be
used by the UE 105 at periodic intervals. In another example, an
operating configuration includes a pool of time resources
represented by a bitmap in which each bit indicates whether a
certain subframe can be used by the UE for transmission. The bitmap
may be repeated periodically and may additionally, in some
embodiments, be associated with a set of transmitting parameters
(e.g., Physical Resource Blocks (PRBs), MCSs) to be used when the
UE is allowed to transmit according to such bitmap.
In some embodiments, the UE 105 may autonomously perform actions
(e.g., activation and/or release actions without direct
intervention by the network 100) that the UE 105 may or may not
indicate by acknowledgement message to the network 100. For
example, in some embodiments, the UE 105 may receive an activation
command and then a release command from the access node 110. In
response, the UE 105 may omit transmission of an acknowledge
indication (e.g., to avoid sending a twice-toggled bit in a
confirmation field, as previously discussed). Alternatively, the UE
105 may send an acknowledgement message with particular content
(e.g., depending on what the bits of the confirmation field
represent in that particular embodiment). Notwithstanding, in other
embodiments the UE 105 may receive an activation command from the
access node 110 and autonomously release associated resources. In
at least some such embodiments, the UE 105 may determine whether or
not an acknowledgement message should be sent, and if so, what the
acknowledgement message contains, e.g., in a manner similar to
embodiments in which each of the actions is commanded by the
network 100. According to other embodiments, the UE 105 may exclude
autonomously performed actions from consideration for
acknowledgement.
FIG. 7A illustrates an example state diagram 700a consistent
according to one or more embodiments of the present disclosure. The
state diagram 700a represents the possible states of an
acknowledgement bit, i.e., a zero or a one. The state diagram 700a
further illustrates whether a UE 105 transmits an acknowledgement
message at a given acknowledgement transmission opportunity
depending on the state of the acknowledgement bit as compared to
the last time the acknowledgement bit was transmitted. As shown, if
the state of the acknowledgement bit has changed from 0 to 1, or
from 1 to 0, the UE 105 transmits the acknowledgment message in the
given acknowledgement transmission opportunity. Otherwise, the UE
105 refrains from transmitting the acknowledgement message in the
given acknowledgement transmission opportunity. Acknowledgment
transmission opportunities may, for example, be periodic and/or
scheduled by the access node 110. Transmission opportunities
according to various embodiments of the present disclosure will be
discussed in further detail below.
The access node 110 may correspondingly expect or not expect an
acknowledgement message from the UE 105 based on which commands the
access node 110 has transmitted. That is, the access node 110 may
determine that, for example, two commands pertaining to the same
cell were both received by the UE 105 because no acknowledgement
message was received in which the bit for that cell was toggled.
Thus, the UE 105 may implicitly acknowledge receipt of the two
commands by refraining from transmitting the acknowledgement
message. Correspondingly, the access node 110 may determine that
both commands were received because the access node 110 expects the
UE 105 to refrain from transmitting an acknowledgement message when
the commands to be acknowledged would cause a confirmation field in
the appropriate acknowledgement message to revert to a previous
state.
Although many of the embodiments described herein use a toggled
bit-field (which can take two values) to acknowledge commands
relating to a particular cell 115 and/or operating configuration,
other embodiments may acknowledge commands using a field that can
represent more than two values (e.g., a confirmation field in which
different values represent respective states). For example, in some
embodiments, a confirmation field supports four values (A, B, C and
D) as illustrated in the state diagram 700b in FIG. 7B. As shown in
the state diagram 700b, according to some embodiments, the UE 105
may refrain from transmitting an acknowledgement message if the
value of the field to be included in the acknowledgement message
represents the same state of the UE 105 prior to receiving the one
or more commands to be acknowledged, according to particular
embodiments. Accordingly, if the state of the UE 105 was B and the
UE 105 performed a series of actions (which may have been triggered
by one or more commands from the network 100) that caused the UE
105 to remain (or change from, and return to) state B, the UE may
refrain from transmitting an acknowledgement message (e.g., similar
to the example of FIG. 7A). Similar principles may apply with
respect to the other examples described herein, when using a field
that can represent more than two acknowledgement values, e.g., fora
particular cell 115 and/or operating configuration.
In other words, if the state of the UE at a time T is A, and the UE
105 performs a set of actions (e.g., performing an activation of
some resources such that the state of the UE 105 is B), the UE 105
may have the opportunity to transmit an indication of the state of
the UE (i.e., B), e.g., using an acknowledgment message as
described above. However, if the UE 105 has performed a series of
actions such that the state of the UE is A again before the
opportunity to transmit the indication of its state occurs (e.g.
first performing an action such that the state of the UE 105
becomes B, and then performing another action such that the state
of the UE becomes A again), the UE 105 may refrain from
transmitting the acknowledgement message, as shown in the state
diagram 700b of FIG. 7B.
In particular, in some radio systems (e.g., LTE and NR) the UE 105
may not be allowed to perform a transmission unless that
transmission is requested from and/or granted by the network 100.
In such cases, the UE's 105 transmissions may generally be under
the control of the network 100. Accordingly, in some embodiments,
upon having an opportunity to transmit (e.g., as granted by the
access node 110), the UE 105 determines whether the state of the UE
105 is different as compared to the most recently reported state,
and if so, the UE 105 transmits an acknowledgement message in which
an indication of the UE's 105 state is provided. For example, if
the UE 105 was initially in state B and the UE performed one or
more actions resulting in that the UE was in state A, the UE would
perform a transmission indicating that the UE's state is A (rather
than B), e.g., to acknowledge the command(s) that caused the UE 105
to be in state A. Alternatively, if the UE 105 performed one or
more actions which resulted in the UE 105 being in state B, the UE
105 would refrain from providing such an indication.
If the toggled bit represents the cell index, the above may happen
for example when the network simultaneously sends more than one
activation/release commands of multiple operating configurations
for the same cell and the UE would need to toggle more than one
time the bit corresponding to the cell index.
If the toggled bit represents an operating configuration index, the
above may happen for example when the network simultaneously sends
more than one activation/release commands of the same operating
configurations in multiple cells and the UE would need to toggle
more than one time the bit corresponding to the operating
configuration index.
Particular embodiments above described a UE 105 that may, upon
reception of a certain command, trigger transmission of an
acknowledgement message in which a certain field is toggled or
changed in value (i.e., as compared to the value of that field in a
previous acknowledgement message). Particular embodiments further
described that multiple commands may be acknowledged using an
acknowledgement message in which a field is toggled or modified a
corresponding number of times (e.g., toggled once per relevant
command to be acknowledged). According to other embodiments, the UE
105 may refrain from transmitting the acknowledgement message if
more than a threshold number of relevant commands require
acknowledgement. This threshold number of relevant commands may be,
in some embodiments, the same as the number of states supported by
the relevant confirmation field. Thus, in some embodiments, a UE
105 using an acknowledgement scheme that uses bit toggling may
refrain from transmitting an acknowledgment message responsive to
receiving more than one command relevant to that bit. Other
embodiments include a UE 105 that refrains from transmitting an
acknowledgement message response to receiving more than a different
number of commands relevant to a particular confirmation field.
Further, as previously discussed, the confirmation field according
to some embodiments may comprise an array of independently
configurable bit-fields (and/or multi-bit fields). In such an
embodiment, each index of the array may be mapped to, e.g., a cell
115 or operating configuration. In some such embodiments, the UE
105 refrains from transmitting the acknowledgement message
responsive to any number of the fields in the confirmation field
toggling (or changing state) more than a threshold number of times.
FIG. 8 illustrates an example process 800 in which a UE 105 uses an
array of bit-fields as a confirmation field included in certain
acknowledgment messages (i.e., when transmitted). Each bit-field in
this example corresponds to a cell 115. As will be further
explained, according to this example process 800, the UE 105
receives one or more commands relating to one or more cells 115,
and transmits an acknowledgment message so long as not more than
one command relevant to each cell 115 has been received since the
last acknowledgement transmission opportunity. The process 800
begins with the UE 105 storing the value of its confirmation field
(block 810). The UE 105 will later use this stored value as a basis
for determining whether or not to transmit the acknowledgement
message. The UE 105 then receives a command from an access node 110
(block 820). In response, the UE 105 toggles the bit corresponding
to the cell to which the command relates (block 830). For example,
if the command is to activate an operating configuration in cell A,
the UE toggles the bit in the confirmation field corresponding to
cell A.
The UE 105 determines whether the bit which was just toggled is
equal to the value of that bit that was earlier stored (block 840).
If the toggled bit has a value equal to the saved value of that bit
(block 840, yes), the UE 105 refrains from transmitting an
acknowledgement message at the next acknowledgement transmission
opportunity (block 860) and begins the process again by storing the
confirmation field value for determining whether or not to transmit
an acknowledgement message in a subsequent transmission opportunity
(block 810).
If the toggled bit is not the same as what was stored (block 840,
no), the UE 105 determines whether an acknowledgement transmission
opportunity has occurred (block 850). If not (block 850, no), the
UE 105 receives the next command (block 820) and proceeds as
described above, toggling the corresponding bit as appropriate
(block 830) and so on.
If, however, an acknowledgement transmission opportunity has
occurred (block 850, yes), the UE 105 transmits an acknowledgement
message (block 870). The confirmation field in the acknowledgement
message includes each of the bits that were toggled since the
confirmation field value was last stored. The UE 105 then restarts
the process 800 by storing the confirmation field value transmitted
in the acknowledgement message for determining whether or not to
transmit a further acknowledgement message in a subsequent
transmission opportunity (block 810).
The UE 105 may refrain from transmitting an acknowledgement in a
number of ways, depending on the embodiment. For example, to
refrain from transmitting an acknowledgement message, the UE 105
may, for example, cancel transmission of a previously triggered
acknowledgement message. Alternatively, the UE 105 may revert to a
state previous to when transmitting the acknowledgment message was
triggered. Thus, in some embodiments, refraining from transmitting
may include the UE 105 taking certain steps towards preparing to
transmit the acknowledgement message (e.g., by generating the
acknowledgement message), but nonetheless refraining from signaling
the acknowledgment message to the access node 110.
Many of the embodiments discussed above include the UE 105
acknowledging commands explicitly (e.g, by transmitting a
particular acknowledgement message that is unambiguous for the
circumstances) or implicitly (e.g., by refraining from transmitting
an acknowledgement message in a manner that can be predicted by the
access node 110). Other embodiments include the access node 110
scheduling the transmission of commands such that the UE 105 is not
presented with having to transmit an ambiguous acknowledgement
message. For example, the access node 110 may schedule the
transmission of commands such that the UE 105 does not receive,
within any acknowledgement period, more commands to acknowledge
than there are states that can be signaled using the corresponding
confirmation field. For example, if a bit-field is used for
confirming commands pertaining to a given cell 115, the access node
110 may schedule no more than one command pertaining to that cell
115 per acknowledgement transmission opportunity. In this way, the
UE 105 may, for example, transmit an acknowledgement message to
acknowledge each command pertaining to that cell 115 using a single
toggled bit. In such a scenario, the UE 105 would not encounter a
situation in which it would need to toggle that cell's 115 bit more
than one time per acknowledgement period. More generally, in some
embodiments, the access node 110 may avoid sending commands within
a given acknowledgement interval that would cause the UE to revert
back to its most recently reported state. According to one
particular example, the access node 110 may avoid sending, in the
same PDCCH occasion, activation and/or release commands of
different operating configurations for the same cell 115 (i.e., if
the bits in the acknowledgement message refer to the cell indexes)
or activation and/or release commands of the same operating
configuration in multiple cells 115 (i.e., if the bits in the
acknowledgement message refer to the operating configuration
indexes).
In another embodiment, the UE 105 may detect whether the correct
number of commands have been correctly received. For example, the
UE 105 may determine the number of commands transmitted by the
access node 110 in the same PDCCH period by reading the size of the
DCI. Alternatively, the UE 105 may determine the number of commands
transmitted by the access node 110 in the same PDCCH period by
reading a flag in the DCI indicating the amount of operating
configurations carried by that DCI.
For example, one particular embodiment of the present disclosure
includes the method 1300 illustrated in FIG. 13. The method 1300 is
performed by a UE 105 configured for use in a wireless
communication system 100. The method 1300 comprises receiving, from
an access node 110, an indication of a number of commands that will
be transmitted from the access node 110 to the UE 105 (block 1310).
The method 1300 further comprises selectively transmitting or
refraining from transmitting an acknowledgement message to the
access node 110 depending respectively on whether or not the UE 105
receives the indicated number of commands within a downlink time
interval to which the indication of the number of commands applies
(block 1320).
In such embodiments in which the UE 105 determines the number of
commands that should be received from the access node 110, the UE
105 may, e.g., trigger (and transmit) an acknowledgement message to
the access node 110 when all of the indicated commands are
correctly received, even in such cases when some bits are toggled
(or changed) more than once (e.g., changed back to a previously
reported state). Alternatively, responsive to one or more commands
not being correctly detected/received, the UE 105 may refrain from
transmitting the acknowledgement message. According to various
embodiments, the indication of the number of commands may be
received in DCI, RRC signaling, a MAC CE, or other signaling from
the access node 110.
In view of all of the above, one or more of the devices and/or
methods described above may be implemented using the example
hardware 900 illustrated in FIG. 9. The example hardware 900
comprises processing circuitry 910 and communication circuitry 930.
The processing circuitry 910 is communicatively coupled to the
communication circuitry 930, e.g., via one or more buses. The
processing circuitry 910 may comprise one or more microprocessors,
microcontrollers, hardware circuits, discrete logic circuits,
hardware registers, digital signal processors (DSPs),
field-programmable gate arrays (FPGAs), application-specific
integrated circuits (ASICs), or a combination thereof. For example,
the processing circuitry 910 may be programmable hardware capable
of executing software instructions stored as a machine-readable
computer program in memory circuitry 920. The memory circuitry 920
of the various embodiments may comprise any non-transitory
machine-readable media known in the art or that may be developed,
whether volatile or non-volatile, including but not limited to one
or more hardware registers, solid state media (e.g., SRAM, DRAM,
DDRAM, ROM, PROM, EPROM, flash memory, solid state drive, etc.),
removable storage devices (e.g., Secure Digital (SD) card, miniSD
card, microSD card, memory stick, thumb-drive, USB flash drive, ROM
cartridge, Universal Media Disc), fixed drives (e.g., magnetic hard
disk drive), and/or any combination thereof.
The communication circuitry 930 may be a controller hub configured
to control the input and output (I/O) data paths of the hardware
900. Such I/O data paths may include data paths for exchanging
signals over a wireless communication network. For example, the
communication circuitry 930 may comprise a transceiver configured
to send and receive communication signals within and/or between the
UE 105, the access node 110, and/or the network 100, e.g., over an
air, electrical, and/or optical medium.
Although some embodiments of the communication circuitry 930 may be
implemented as a unitary physical component, other embodiments of
the communication circuitry 930 may be implemented as a plurality
of physical components that are contiguously or separately
arranged, any of which may be communicatively coupled to any other,
and/or may communicate with any other via the processing circuitry
910. For example, in some embodiments, the communication circuitry
930 may comprise transmitter circuitry (not shown) configured to
send communication signals, and receiver circuitry (not shown)
configured to receive communication signals. According to
particular embodiments, the hardware 900 illustrated in FIG. 9 may
be configured with a plurality of components. These components may
include a plurality of communicatively coupled hardware units
and/or software modules. One or more of the hardware units may be,
e.g., part of the processing circuitry 910. One or more of the
software modules may be, e.g., stored in the memory circuitry 920
and executed by the processing circuitry 910.
For example, the hardware 900 may be comprised in a UE 105 and
configured with the example components 950a illustrated in FIG. 10.
The components 950a include a first acknowledging unit or module
1010 and a second acknowledging unit or module 1020. The first
acknowledging unit or module 1010 is configured to acknowledge one
or more first commands received from an access node 110 by
transmitting, to the access node 110, a first acknowledgment
comprising a confirmation field set to a first value. The second
acknowledging unit or module 1020 is configured to, after the first
acknowledging unit or module 1010 acknowledges the one or more
first commands, acknowledge one or more second commands received
from the access node 110 by selectively transmitting or refraining
from transmitting, to the access node 110, a second acknowledgement
comprising the confirmation field set to a second value depending
respectively on whether or not the second value would be different
from the first value.
The hardware 900, when comprised in the UE 105, may additionally or
alternatively be configured with the example components 950d
illustrated in FIG. 14. The components 950d include a receiving
unit or module 1410 and a transmitting unit or module 1420. The
receiving unit or module 1410 is configured to receive, from an
access node 110, an indication of a number of commands that will be
transmitted from the access node 110 to the UE 105. The
transmitting unit or module 1420 is configured to selectively
transmit or refrain from transmitting an acknowledgement message to
the access node 110 depending respectively on whether or not the UE
105 receives the indicated number of commands within a downlink
time interval to which the indication of the number of commands
applies.
Alternatively, the hardware 900 may be comprised in an access node
110 and configured with the example components 950b illustrated in
FIG. 11. The components 950b include a transmitting unit or module
1110, a first determining unit or module 1120, and a second
determining unit or module 1130. The transmitting unit or module
1110 is configured to transmit, to a UE 105, one or more first
commands and subsequently one or more second commands. The first
determining unit or module 1120 is configured to determine that the
UE 105 received the one or more first commands by receiving, from
the UE, a first acknowledgement comprising a confirmation field set
to a first value. The second determining unit or module 1130 is
configured to determine that the UE 105 received the one or more
second commands by receiving or not receiving, from the UE 105, a
second acknowledgement comprising the confirmation field set to a
second value depending respectively on whether or not the second
value would be different from the first value.
The hardware 900, when comprised in the access node 110, may
additionally or alternatively be configured with the example
components 950c illustrated in FIG. 12. The components 950c include
a interfacing unit or module 1210 and a scheduling unit or module
1220. The interfacing unit or module 1210 is configured to transmit
a first set of commands to a UE 105 and receive a first
acknowledgement from the UE 105 in response. The first
acknowledgement comprises a confirmation field set to a first
value. The scheduling unit or module 1220 is configured to schedule
transmission of a second set of commands to the UE 105 according to
one or more rules that require the UE 105 to respond with a second
acknowledgement comprising the confirmation field set to a second
value that is different from the first value.
The present invention may, of course, be carried out in other ways
than those specifically set forth herein without departing from
essential characteristics of the invention. The present embodiments
are to be considered in all respects as illustrative and not
restrictive, and all changes coming within the meaning and
equivalency range of the appended enumerated embodiments are
intended to be embraced therein.
* * * * *